I need help (also ama)

So, my pup broke the one rule we have set for him (ftm) twice, which is that he isn't allowed to touch himself without my permission, so far I've been making him not wear a bra, but I feel like since it happened twice there should be more severe punishment, we dont live together currently and I'm traveling for the weekend, all suggestions are welcome, spanking has definitely crossed my mind, but idk how comfortable he is with it. Anyways, please suggest a punishment, and ask any question you like :3 nsfw or sfw